CAPE TOWN (AFP) - South African icon Nelson Mandela, 93, underwent a diagnostic probe for an abdominal problem and is doing 'fine' on his second day in hospital on Sunday, Defence Minister Lindiwe Sisulu said.

'He had investigative laparoscopy,' a procedure in which the abdominal area is probed by tiny cameras inserted through small incisions, Ms Sisulu told a press conference.

'He's fine, he is recovering from anaesthetic and he is as fine as can be at his age. He is fine and handsome.'

Ms Sisulu, whose ministry is responsible for the medical treatment of the former statesman, would not say when Mr Mandela would be released, with officials also keeping secret the name of the hospital where he is being treated.